Improvement in furnace-grates



W. TINKHAM.

Furnace-Grate.

Patented Aug. 10, 1875.

INVENTUR ATTDBNEYS.

mPEKERs, mioruumosiuruin, WASHINGTON. D Q

UNITED STATES PATENT OFFICE.

WILLIAM TLNKHAM, OF PROVIDENCE, RHODE ISLAND.

IMPROVEMENT 'IN FURNACE-GRATES.

Specification forming part of Letters Patent No. 166,487, dated August10, 1875; application filed December 28, 1874.

To all whom it may concern Be it known that I, WILLIAM TINKHAM, of thecity and county of Providence, Rhode Island, have invented a new anduseful Improvement in Furnace-Grates, of which the following is aspecification: The desiderata in furnace-grates are maxiprovide a gratewhich shall possess these qualities, and to this end I adopt theconstruction hereinafter described.

Figure 1 is a side view of the grate; and Fig. 2 is a cross-section ofFig. 1, taken on the line as w.

Similar letters of reference indicate corresponding parts.

A represents the grate-bar, any number of which, placed together as seenin Fig. 2, form the grate. On one side of each bar are one or moreconical points, B, and on the opposite side, corresponding in positionwith the conical points B, are conical sockets G, which receive thepoints B, as represented in Fig. 2. This arrangement makes the grateself-supporting,

while the point of contact is reduced to a minimum. D are conical lugscast on the side of the bar, which extend from one bar to the next, andserve to keep the bars steady and in an upright position. E representsthe cap of the bar, which is of convex form, the convex side beingconnected with the bar A, the

concave side being uppermost, as seen. This concave side Will naturallyfill with ashes and prevent the web or bar from becoming overheated.From the cap down the bar or web is broad and thin, and is supported bythe conical points and sockets, and by the conical lugs D.

The point and socket B 0 may be made of one piece, inserted through thebar, a socket on one side, and a conical point on the other; or they maybe placed on the bar, and more or less in number he used.

Instead of the lugs D there may be sockets and points to support thelower part of the grate; but I prefer the arrangement shown. F and G arethe bearingpoints of the grate.

By constructing the grate in this manner the web A may be made very thinand light, and be fully supported to render it desirable. The points ofcontact are so extremely small that they present no obstruction to thedraft, nor a mass of iron to absorb heat and affect the web.

I do not claim a grate-bar provided with- WILLIAM TINKHAM.

Witnesses:

FRANKLIN METCALF, F. W. GRAMMONT.

